Patent GB-372640-A (GB)
Title: Manufacture of indigoid vat dyestuffs
IPC: C09B7/00
Filed: 1931-08-10
Abstract: Unsymmetrical indigoid dyestuffs are obtained by condensing a 5-methyl-6-halogen-3-oxythionaphthene or a 2-derivative thereof with any indigoid component other than 5-methyl-6-halogen-3-hydroxythionaphthene or a 2-derivative thereof. The resulting dyestuffs may be halogenated.  In examples: (1) 5-methyl-6-chlor (or brom) -3-oxythionaphthene is condensed in alcohol, with acenaphthenequinone; (2) the resulting dyestuff is brominated in nitrobenzene; (3) 5-methyl-6-chlor-3-oxythionaphthene-p-dimethylaminoanil or 5-methyl-6 - chlor-3 - oxythionaphthenequinone is condensed with 4-methyl-6-chlor - 3 - oxythionaphthene; (4) 5-methyl-6-chlor-3 - oxythionaphthene-p-dimethylaminoanil is condensed with 2 : 1-naphthoxythiophene; (5) cotton is dyed scarlet in a bath obtained by vatting the dyestuff prepared according to example (1).  The dyeing of wool, silk, and artificial silk is referred to.  The use of the halides and the oximes of 5-methyl-6-halogen-3-oxythionaphthenequinone and of 5-methyl-6-halogen-3-oxythionaphthene-2-carboxylic acid is mentioned, and also the properties of the dyestuffs prepared from 5-methyl-6 - chlor-3 - oxythionaphthene and the following components; a -isatinanilide, 5 : 7 - dibromisatinchloride, 5 : 7 - dibromisatin, 3 - oxythionaphthene-p - dimethylaminoanil, 5 - chlor-7-methyl - 3 - oxythionaphthene-p-dimethylaminoanil, 6-ethoxy-3-oxythionaphthene-p-dimethylaminoanil, 1 : 2-naphthoxythiophene-p-dimethylaminoanil, 2 : 3-napthoxythiophene-p-dimethylaminoanil, and 1-chlor2 : 3-naphthoxythiophene-p-dimethylaminoanil.  5-Methyl-6-chlor (or brom)-3-oxythionaphthene may be prepared by treating 1-methyl-2-chlor (or brom)-4-phenylthioglycollic acid, in chlorbenzene with phosphorus trichloride, and heating with aluminium chloride after decanting from the phosphoric acid mud.  5-Methyl-6-chlor (or brom)-3-oxythionaphthene-p-dimethylaminoanil is prepared by treating a caustic soda solution of the parent oxythionaphthene with a solution of p-nitrosodimethylaniline in alcohol.  By treatment with sulphuric acid, the anils yield the corresponding quinones. 1-Methyl-2-chlor (or brom)-4-phenylthioglycollic acid may be prepared by reducing 1-methyl-2-chlor (or brom)-benzene-4-sulphochloride with zinc dust, treating the resulting zinc sulphinate with sulphuric acid and condensing the 1-methyl-2-chlor-4-thiophenol, which may be separated by steam distillation, with chloracetic acid.  The Specification as open to inspection under Sect. 91 (3)(a) comprises also the production of unsymmetrical indigoid dyestuffs by condensing a compound having the formula:-- <FORM:0372640/IV/1> in which one x represents an alkyl group and the other a halogen, and y a reactive group, with any suitable indigoid component.  The following additional examples are given: (1) 5-chlor-6-methyl-3-oxythionaphthene is condensed with 5 : 7-dibromisatinchloride; (2) the resulting dyestuff is brominated; (3) 5-chlor-6-methyl-3-oxythionaphthene is condensed with 5 - chlor - 7 - methyl - 3 - oxythionaphthene-p-dimethylaminoanil; (4) 5-brom-6-methyl-3-oxythionaphthene is condensed with acenaphthenequinone; (5) 5-chlor-6-methyl-3-oxythionaphthene-p-dimethylaminoanil is condensed with 2 : 1-naphthoxythiophene.  The properties of the dyestuffs prepared by condensing 5 - chlor - 6 - methyl - 3 - oxythionaphthene with the following components are also stated; a -isatinanilide, 5-brom-a -isatinchloride, 6-chlor-3 - oxythionaphthene - p - dimethylaminoanil, 4- methyl - 6 - chlor - 3 - oxythionaphthene-p - dimethylaminoanil, 5 : 7 - dibromisatin, 1 : 2 - naphthoxythiophene - p - dimethylaminoanil and 2 : 3-naphthoxythiophene-p-dimethylaminoanil. 5-Halogen-6-methyl-3-oxythionaphthene may be made by diazotising 5-methyl-4-halogen-2-aminobenzene-1-sulphonic acid, treating with cuprous cyanide to obtain 5-methyl-4-halogen-2-cyano-1-benzenesulphonic acid, converting the latter first to the corresponding 1-sulphochloride by means of phosphorus pentachloride and then to the 1-thiophenol by reduction with zinc, which simultaneously hydrolizes the cyano group, and condensing the resulting 5-methyl-4-halogen-2-carboxythiophenol with chloracetic acid.  The oxythionaphthene is obtained by heating with caustic soda.  This subject-matter does not appear in the Specification as accepted.